<!DOCTYPE html>
<title>IntersectionObserver observing an SVG &lt;rect> with fractional bounds element</title>
<meta name="viewport" content="width=device-width,initial-scale=1">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/intersection-observer-test-utils.js"></script>

<svg id="container" width="1" height="1" viewBox="0 0 1000 1000" style="background: lightblue; position: absolute; top: 0; left: 0;">
  <rect id="target" x="0" y="-3" width="4" height="4" fill="green"></rect>
</svg>

<script>
  setup(() => {
    window.entries = [];
    window.target = document.getElementById("target");
    window.targetRect = target.getBoundingClientRect();
  });
  var epsilon = 0.0001;
  runTestCycle(function() {
    assert_true(!!target, "target exists");
    var observer = new IntersectionObserver(changes => {
        entries = entries.concat(changes);
      }, {root: container, threshold: [0, 0.25, 0.5, 0.7, 1]});
    observer.observe(target);
    entries = entries.concat(observer.takeRecords());
    assert_equals(entries.length, 0, "No initial notifications");
    runTestCycle(step0, "Initial Observation");
  });
  function step0() {
    target.setAttribute('y', -2);
    runTestCycle(step1, "Changing target y position to -2 (-0.002 in root coordinates)");
    checkLastEntry(entries, 0, [
      0, 0.004, -0.003, 0.001,
      0, 0.004, 0, 0.001,
      0, 1, 0, 1,
      true,
    ], epsilon);
  }
  function step1() {
    target.setAttribute('y', -1);
    runTestCycle(step2, "Changing target y position to -1 (-0.001 in root coordinates)");
    checkLastEntry(entries, 1, [
      0, 0.004, -0.002, 0.002,
      0, 0.004, 0, 0.002,
      0, 1, 0, 1,
      true,
    ], epsilon);
  }
  function step2() {
    target.setAttribute('y', -4);
    runTestCycle(step3, "Changing target y position to -4 (-0.004 in root coordinates)");
    checkLastEntry(entries, 2, [
      0, 0.004, -0.001, 0.003,
      0, 0.004, 0, 0.003,
      0, 1, 0, 1,
      true,
    ], epsilon);
  }
  function step3() {
    target.setAttribute('y', 0);
    runTestCycle(step4, "Changing target y position to 0");
    checkLastEntry(entries, 3, [
      0, 0.004, -0.004, 0,
      0, 0.004, 0, 0,
      0, 1, 0, 1,
      true,
    ], epsilon);
  }
  function step4() {
    checkLastEntry(entries, 4, [
      0, 0.004, 0, 0.004,
      0, 0.004, 0, 0.004,
      0, 1, 0, 1,
      true,
    ], epsilon);
  }
</script>
